The book likely represents the public views of one of Yusuf’s sons and the current ISWAP leader, Abu Musab al-Barnawi, who became very close to Abubakar Shekau after the former’s father was killed in 2009.

Antibiotics are facing an existential crisis less than a century after their introduction. Increased bacterial resistance is putting the world at risk of an era in which routine infections are untreatable.